1. Field of the Invention
The disclosure relates to an optical touch control device and a method for determining a touch coordinate, and more particularly, to an optical touch control device and a method for determining a touch coordinate via utilizing a single optical sense module to obtain an image data.
2. Description of the Prior Art
The touch control device has been widely utilized among electrical products. There are four types of the common touch control device, such as the resistive type, the capacitive type, the surface acoustic wave type and the optics type, and each type of the touch control devices provides different accuracy, so as to be selected for different users' requirements. In the prior art, the optics type touch control device utilizes a plurality of optical sense modules to detect a touch coordinate relative to a touch object.
Please refer to FIG. 1, which illustrates a conventional schematic diagram of an optical touch control device 10. As shown in FIG. 1, the optical touch control device 10 installs a plurality of light source bars 1000, 1002, 1004, 1006 surrounding a touch control panel 104, so as to generate a plurality of light source signals within spatial boundaries of the touch control panel 104. Optical detectors 1020, 1022 are installed along one side of the optical touch control device 10, so as to receive the plurality of light source signals. When a touch object, e.g. a finger F, appears within the spatial boundaries of the touch control panel 104, the finger F may partially block the plurality of light source signals generated by the plurality of light source bars 1000, 1002, 1004, 1006, so as to generate a shadow zone corresponding to the finger F. Under such circumstances, the optical detectors 1020, 1022 obtain a first image data and a second image data containing the shadow zone, respectively. The first image data and the second image data render distances between the finger F and the optical detectors 1020, 1022 according to a signal analysis of the shadow zone. Further, the distances between the finger F and the optical detectors 1020, 1022 are inputted into the triangulation location technique to estimate the position of the finger F relative to the touch control panel 104.
As can be seen from the above, the optical touch control device 10 must utilize the plurality of optical detectors to satisfy the condition of the triangulation location technique, so as to estimate the position of the touch object. On the one hand, the production cost may increase. On the other hand, the plurality of optical detectors must synchronize to obtain the image data, or additional comparison circuits may be installed to process differences of the image data. Therefore, it is an important issue to appropriately reduce the number of the optical detectors as well as to effectively simplify the calculation complexity of the image data.